I bought this alleged ‘wreck’ primarily to have another demonstration object for my Geiger counter, without bothering too much what it is and from when. It really let’s the needle swing on alpha particles, beta particles and gamma rays.
But then, it showed surprisingly good readings on the time scale. Of course, I could not resist to open the back to see what movement it has inside, so different from the outside appearance.
There is absolutely no marking on the movement whatsoever to lead me any further, not a number, nothing. The only exception: It says 20 jewels, but it's marked 21 jewels outside on the dial. I guess the movement had been swapped at some stage (perhaps with a spacer to make it fit), and most likely also the crown.
The diameter is about 22mm, which would be 9.75’’’ (lines). Beats per second on the timegrapher: 18.000. I went up and down and sideways (plus advanced search) in the Ranfft database, but had to finally give up and come here for possible help. I also found nothing reliable on the Anker brand, there is just to much with that designation around. And finally, that logo on the case back is something I have never seen before.